Although Telegram has terminated its blockchain project, Telegram Open Network (TON), in May 2020, the TON test net has been apparently running for almost one year.
In a July 6 update, the official TON development group on Telegram announced that it would be discontinuing its support of the test network for TON. Remaining TON validators will be turned off by August 1. In the post, the TON official recommended network participants save all their relevant data and stop their testing processes.
Despite the testnet being set to shut down less than a month from now, network participants will still be able to continue their experimentation after the testnet is terminated. In order to do that, users can install their own testnet validators, described in greater detail in three different how-to documents containing guidelines for the Full Node, the Validator, and Test Grams.
thanks for updatation